I bought this truck used, equipped with a K&N cold air filter and performance exhaust. I have always used a performance exhaust but this was my first experience with the cold air solution combined. The performance is impressive but my ears ring and the oscillation ring frequency was too much for me. Having used K&N filters on all my vehicle stock air intakes for years I know that there is a K&N alternative. I went back to a stock intake filter system using this stock replacement filter. I cannot feel any decrease in performance and the oscillation is gone.